J. Hector St. Jean de Crevecoeur's "Letters from an American Farmer"

fecundity

fe·​cund ˈfe-kənd  ˈfē- 
Adjective
1
fruitful in offspring or vegetation PROLIFIC
a fecund breed of cattle
2
intellectually productive or inventive to a marked degree
a fecund imagination
a fecund source of information

Source